document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=943917>Question 943917</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How many terms are in the sequence: 640,320,160,.......,5? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #575523 by </B><A HREF=/tutors/aboutme.mpl?userid=dkppathak><B>dkppathak(439)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=dkppathak><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=dkppathak><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=575523\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How many terms are in the sequence: 640,320,160,.......,5?<BR>\n" );
document.write( "it is gp whose a=640   r=1/2=2^-1  n=? last terms is=5<BR>\n" );
document.write( "last term =ar^n-1<BR>\n" );
document.write( "5=640x(1/2)^n-1<BR>\n" );
document.write( "5/640 =2^-n+1<BR>\n" );
document.write( "1/128=2^-n+1<BR>\n" );
document.write( "2^-7=2^-n+1<BR>\n" );
document.write( "-7=-n+1<BR>\n" );
document.write( "-7-1=-n<BR>\n" );
document.write( "n=8 </SPAN>\n" );
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